HERBIE! Journeys on our narrowboat and the trials and tribulations of maintaining her.

Tuesday, March 26, 2013

More on that engine and life aboard another kind of boat

By jove, I’ve got some clever readers out there. Either that or I gave too many clues. Yes, the engine I showed yesterday was a torpedo engine of the type used in WWII and afterwards. What an amazing piece of kit, ten times the horsepower of yer average modern narrowboat engine, burning hardly any air, and fitting neatly inside a twenty one inch tube. Of course it only had a running life of a minute or two, so I don’t suppose they were built to last. The torpedos were fired out of the tubes using compressed air, how and when the propulsion motors were started I have no idea.

Its a Brotherhood Burner Cycle engine, built by the old firm Peter Brotherhood still going today in Peterborough. I went there myself a few years back, but never realised they had made an engine like this. Nowadays they are still making innovative engineering products for more peaceful purposes like wind turbine stuff and combined heat and power plants.

I think this is a picture of the same torpedo engine with the prop shaft

Air pressurized to about 840 lbs./in2 (59 kg/cm2) was heated to about 1,800ºF (1,000ºC) by burning a small amount of atomized kerosene-type fuel. This hot air/gas mixture was then fed into the engine via poppet valves and more fuel was injected into each cylinder a little before TDC (Top Dead Center). The spontaneous ignition of this mixture powered the engine.

Looking at the foot of the page that the link above refers to, I see that 4 out of every 5 torpedos fired by submarines missed their targets!

I saw it when I went last week to the Royal Naval Submarine Museum in Gosport. A fascinating place. You get a guided tour of the 1947 sub HMS Alliance and you can’t help drawing comparisons with life aboard a narrow boat. In some respects a similar sort of space except that it is actually bursting with pipes, cables, handwheels, and of course the big main propulsion engines which strangely have a smaller horsepower than the torpedo engines. Its the old torque / engine speed thing. The same reason why a big heavy old working boat with 18hp engines leaves us in the dust with our 40 hp engine when we come out of a lock.

How do you fancy sorting out a wiring or plumbing problem amongst this lot?

This ship boat had crew of sixty plus submariners. I imagine there was little privacy! The galley, which was operated by two cooks was a good bit smaller (really) than the galley on most narrowboats yet reputedly the grub they dished up was pretty good. Apparently the men never bathed on board, water was too short. Everybody smelled the same I suppose so they might not notice!

As you know, no talk of boats can exclude reference to toilets and batteries, so here goes. The loos were not unlike the pumpout loos on many narrowboats except that to operate them you had to open and close various valves in the right order to get suction pressures right. Supposedly, failing to do this correctly was the origin of the term “getting your own back”. Enough said.

There was of course a huge bank of wet cell batteries under the floor. These were charged by the main engines when the boat was at the surface (or just under, using a snorkel to breathe the engine), and then the batteries would drive the boat’s electric propulsion motors when they went deep and quiet.

Elsewhere in the museum we looked into a “miniature submarine”, more narrowboat size I suppose. There were used for sneak attacks or reconnaissance missions in harbours and the like, and were not for living on for any length of time. There we saw an old friend- a Gardner engine

reportedly the same model they used to use in London buses but it wouldn’t surprise me to see one in a narrowboat somewhere.

All in all a brilliant museum, and yet another reason to visit dear old Pompey.

And that reminds me. On Thursday at the Leopold tavern in Albert Road, Southsea I had what might well be the best pint of beer I have ever had in my life (and I have drunk one or two in my time). Dark Star American Pale Ale, completely and absolutely stunningly delicious. The Leopold does look after its beer very well. So there’s another reason to visit Pompey.